92 OPTICAL PROJECTION 



vapour has been employed in lieu of hydrogen or house-gas in 

 the oxy-hydrogen jet. The fluid first employed was sulphuric 

 ether. To vapourise this by heat would be terribly dangerous ; 

 but it is found that passing fine streams of air through an ade- 

 quate quantity of fluid carries over with it a sufficient quantity 

 of vapour to burn as a combustible without being explosive. 

 The same occurs with a stream of oxygen ; therefore if the 

 oxygen supply (from bag or cylinder) be divided into two 

 branches, one of these passing through the ether will convey 

 combustible vapour to the jet, whilst the other branch may 

 be adjusted to supply the most calorific proportions at the 

 nipple, in the usual manner already described. 



The oxy-ether light is thus adapted for use in just such 

 halls, without gas, as found employment fortheoxy-spiritjet, 

 but with the advantage of a far more powerful light. This 

 light has been chiefly brought into notice in England by Mr. 

 W. Broughton, of Manchester, and the late Eev. F. Hardwich, 

 who have worked a great deal in concert ; and in the United 

 States by Mr. Frank Ives, of Philadelphia, who advocates 

 a different form of apparatus. 



Mr. Broughton adopted a tank of ether, using first of all 

 an apparatus essentially like a wash-bottle for washing oxygen, 



but forcing the 

 oxygen through a 

 number of very 

 fine apertures. 

 This failed to satu- 

 rate with vapour, 

 and gave a flicker- 

 ing flame. Next, 



a tallk WaS 



fca.54.-Man of Tank . 



with horizontal 



divisions, the oxygen being compelled to travel backwards and 

 forwards gathering vapour. Finally, both Mr. Broughton and 

 Mr. Hardwifch adopted a tank furnished with perpendicular 



